Given the
fixture is
Altman because there was a lot of fixtures very similar to it, the radial mount lamp
base would be what you describe to a
Altman #360 which is pre
360Q or Quartz/
halogen series. In other words, the
fixture was designed for the larger
incandescent T-20 (2.1/2" wide) bulbs thus the large cutout in the
reflector and long length of the lamp
base to the
focal point due to lamp cooling needs. Needed the extra space for letting the
bulb cool sufficiently given the wattage. It’s lamp was also off center because the original
incandescent lamps such as the DNS or DEB were designed to burn
base up ±30° due to
filament sagging/support requirements. Having the lamp off at an angle allowed for this in most hang positions. It’s still a good rugged
fixture and it’s design was revolutionary for it’s time given the purpose is to put focused light on the
stage.
It is using the same lamp
base as a
Fresnel a medium
prefocus (P-28s), and this is a standardized design.
Altman probably buys from the same source as from who StagedoorTD buys his from, or those sources buy from
Altman. There is only a few companies making this lamp
base and all are good in quality as far as I know. I expect it’s from Sylvania,
Altman (who ever is making it for them), Bender or Wirth, otherwise use of a lamp
base other than that might void the UL listing given these are the listed lamp
base manufacturers for the
Altman 360Q so it’s safe to assume the same companies would be authorized to make the #360 lamp
base. Though I think
Leviton also makes the P-28s and it would be fine and listed for the
fixture I would assume. Ushio should also make the lamp
base though it might not be authorized for use in the
fixture given their Medium
Bi-Pin (G9.5) lamp bases are not authorized for use in the #
360Q.
As for the lamp itself, because it’s a
halogen upgrade to a
incandescent lamp, the standard
Fresnel BTL series lamp will not be extended enough in length to match up to the focal center of the
fixture. Unlike with the
360Q axial mounted lamp
base series, after the initial
incandescent to
halogen upgrade to the lamp, there has been no further improvements to the lamp so it’s always going to be a little less bright and you can’t put in the FLK series of 115v lamps to brighten it up. There is that detail of the huge hole in the
reflector anyway in the way of efficiency.
Still it’s a decent
fixture to put light on the
stage. Plan on using it for the more amber lighting and less bright/intense backup lighting and it should prove very useful. One thing you could probably do to improve it’s output is to check to see if the
fixture has green or blue lenses. If they appear greenish in color, better quality replacement lenses would be worth the investment if you intend to keep the
fixture. This will provide a more clean white light output. You should also have standardized parts for
lens trains so such fixtures could easily fit into the normal inventory no matter what position used at given a
lens train swap. It's probably been 5 years since I last touched a radail
leko so there are things I would tend to forget for sure about.
As opposed to a
Fresnel lamp having a lamp center length of 2.3/16", this
fixture will center with a 3.1/2" lamp. You cannot use a
Fresnel lamp in a #360
fixture, unless stagedoorTD is implying he is
blocking up the
fixture’s lamp
base by 1.5/16" in which case it would probably very successfully take a standard BTL series
Fresnel lamp. I don’t recommend doing this however without expert supervision especially in a school because it would void the UL listing for the
fixture. Note also that the BTL series of lamp is for all intensive purposes also a
dead end. There is no further improvements planned for it.
There are many lamps for the #360
fixture. Many are becoming more and more rare to find, other’s are high output but too short in life.
The EGE is the primary 500w/120v
halogen upgrade lamp for the
fixture. There are some very slight differences in output and
color temperature, but in this
fixture I don’t think you will be able to tell the difference. Go for what’s cheapest between GE, Philips, Osram, Ushio and Wiko. I believe they all still make this lamp, though I did not see it listed from Osram recently. I do not know how many more years the lamp will be made from any of them however.
The best lamp you can put in the
fixture would be a 750w/120v EGG
halogen lamp. Again, go for the above companies in who is cheapest and I don’t know how much longer at least GE, Osram and Philips will continue making the lamp. My theory is that this lamp in the #360 should about approximate the output of a normal #
360Q fixture with upgraded 575w lamp to GLA or HX-601 for long life. It might be a
bit more dim in
color temperature but the output will be about the same given the higher wattage.
There are quite a
bit of other lamps available for the
fixture including 1Kw lamps, but I would stick with these two.
Should you need parts for the
fixture, and given
Altman no longer sells the parts at least for the lamp
base casting because the rest of the parts would be similar to the
360Q, than I repentantly had it confirmed that Varalight/
Hub/Dimatronics in the Chicago area still exists as a company and it was known as a retailer for old
fixture parts. They would easily have parts for the #360.